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Posted by wmmbb in carbon emissions, Global Warming (climate change).

Reading the blog Catallaxy is like entering an alternative reality, and commenting can be both weird and productive. For one thing be prepared for the personal attacks.

When were they ever wrong about anything? Perhaps always, and if true, they would be oblivious. Since they draw exclusively and partially on self-supporting sources, and since the ideology is at odds with mine, it has the sense of an alternative reality.

I am astonished how basic logical principles get thrown out the door and under the bus. Arguing against the person is standard fare. The in-your-face subtlety of reducing an argument to absurdity is occasion for a personal attack.

These faults may be my faults as well, but I try adhere to the principle of offering alternate and contrasting views. It is reasonable to rely on expert opinion, but not to be selective, or to suppose that all experts are equally expert. My incompetence across the relevant areas in not in doubt, nor immediately or easily remedied. Keep that qualification in mind.

There is a vicarious, albeit trivial, satisfaction in undermining the status quo by offering up conventional wisdom. As a direct result of commenting there I referenced this recent presentation to the AGU by Ray Pierrehumbert:

He was dismissed by one comment as part of “the Real Science cabal”. I infer that this person did not listen to the hour-long presentation. However, to give due credit, Bruce of Newcastle did. He evidently understands the science. He put the concise case for the non-warming proposition:

The point about GHG theory is that global warming can be large and dangerous or small and harmless.

The IPCC claims large and dangerous. This is not supported by the data. For example the current temperature trend is down, not up, which cannot be explained if CO2 has the large net effect claimed for it.

The net effect is the important one. If CO2 was left alone to do its thing (ie the Arrhenius calculations) it would cause a 1.1-1.3 C rise per doubling of concentration.

But measured 2XCO2 is about 0.6 or 0.7 C per doubling. Which means only a small rise.

And that is why the temperature is slightly falling, because solar activity has slowed and the oceanic cycle has flipped over to the cooling phase, which overcomes the small net impact of CO2.

That is the empirical view, which as it happens fits the data very well indeed, whereas the IPCC computer models have failed notwithstanding Dr Pierrehumbert’s spin.

It is actually harmful for the left of politics to keep pushing the CAGW line in the face of real world data because it discredits the whole progressive message. I recommend to people of the left side of politics to ditch CAGW while you can and move to a different cause.

The case is made is commendable clarity and the assumptions are clear. Equally clearly, without attributing personal factors, that those that we would objectively assess as having both expertise and close engagement with the full evidence do not share those assumptions. And yet they have tended to be conservative, it is claimed, and so under estimated the consequences of global warming.

I really have not followed the climate change dispute, as I had been told. I had not grasped that position adopted is to deny the fundamental principle that changing the atmosphere by increasing the proportion of greenhouse gases, principally Carbon Dioxide, acts to change the climate system. Much like going to the doctor, I tend to rely on the scientists actively working in the field. My cardiologist actually did the biopsy of my spleen, and I suppose like my kidney specialist works cooperatively with other specialists. I tend to rely on their advice.

That said, if CO2 is having a minimal or marginal effect how can the temperature rise of the past hundred years, the melting of Arctic ice cap, Greenland and Antarctica, the increasing acidification of the oceans and the threat of the coral reefs, rising sea level among other observed phenomena be explained? Is there any indicator that does not point to climate change? The actual details of climate change are affected by the dynamics of the system, which I believe is increasingly understood. Contrary to what is claimed the computer models have been successful in predicting the onset of La Nina, which in itself is quite an achievement. Changes in the behavior of the Southern Oscillation Index, shifts in the jet stream, and the frequency of extreme weather events, which I would ascribe as sub system systemic changes are not mentioned.

Matt Ridley, via Sinclair Davidson, claims in The Wall Street Journal that “evidence” points to a rise of just one degree Celsius by 2100. “The net effect on the Planet may actually be beneficial”. Nic Lewis the inside source for these conclusions is repeating what he has said before. MattRidley reports:

Mr. Lewis tells me that the latest observational estimates of the effect of aerosols (such as sulfurous particles from coal smoke) find that they have much less cooling effect than thought when the last IPCC report was written. The rate at which the ocean is absorbing greenhouse-gas-induced warming is also now known to be fairly modest. In other words, the two excuses used to explain away the slow, mild warming we have actually experienced—culminating in a standstill in which global temperatures are no higher than they were 16 years ago—no longer work.

In short: We can now estimate, based on observations, how sensitive the temperature is to carbon dioxide. We do not need to rely heavily on unproven models. Comparing the trend in global temperature over the past 100-150 years with the change in “radiative forcing” (heating or cooling power) from carbon dioxide, aerosols and other sources, minus ocean heat uptake, can now give a good estimate of climate sensitivity.

The conclusion—taking the best observational estimates of the change in decadal-average global temperature between 1871-80 and 2002-11, and of the corresponding changes in forcing and ocean heat uptake—is this: A doubling of CO2 will lead to a warming of 1.6°-1.7°C (2.9°-3.1°F).

This is much lower than the IPCC’s current best estimate, 3°C (5.4°F).

Mr. Lewis is an expert reviewer of the recently leaked draft of the IPCC’s WG1 Scientific Report. The IPCC forbids him to quote from it, but he is privy to all the observational best estimates and uncertainty ranges the draft report gives. What he has told me is dynamite.

The evidence is conclusive. One expert reviewer has conclusively disproved calculations previously held of the radiative forcing of Carbon Dioxide, without any reference to any dissenting view, expert or otherwise. The models of the climate system are wholly wrong, obviously because they were designed by incompetent people who never tested them. The fossil fuel industries, happily now and in good conscience, can go on polluting the atmosphere, and in fact it would be better is they did.

I would not expect that chance of error was inherent, but that over time they would be refined. What is explained? How did the heat get into the ocean?

I much prefer the science in which propositions are explicit and tested, then subject to expert review and published and from which the findings and methods of any study can be further tested by new studies. Furthermore all relevant and possible causes are evaluated. The problem with climate change denial includes feel-good conclusions, partial information, self-serving methods, spurious claims of reliability, and failure to address the possible consequences of global warming.

Clearly, this is an opinion. We non-experts have to make judgments.


To contrast with the argumentative ju jitsu of climate denial, here is the grim, but optimistic sounding James Hansen with the loaded climate dice:

A troika of scientists discuss Climate Change and the Problem of Climate Sensitivity at the European Geophysical Union:

Here is Stephen Schneider on Climate Change, including comments about risk management.

Stephen Schneider again, addressing the home base at Sanford and making sense of what passes for a ” scientific ” debate that respects the full range of evidence:

Then this, if it works:



1. Bruce of Newcastle - December 20, 2012

Wmmbb – Thankyou for your kind comments. Yes, Catallaxy is quite rough at times, being a libertarian blog they have a very light moderation touch.

Apology for the hard time you received. I am a relative newcomer to that blog, but many of the regulars have had run ins with very strong minded CAGW proponents for many years, and they’re a bit touchy on the subject. On the other hand the advantage of such lightly moderated blogs is you can run free range discussions and the moderators tend not to intervene, whereas you cannot have a discussion between climate sceptics and CAGW proponents on blogs such as Skeptical Science and Real Climate, as the moderators often delete the climate sceptics posts.

Also an apology that I am posting this anonymously. I risk significant problems if I were to post under my name, as I work in science and even in the climate space from time to time. My training is as a chemist, I work in R&D and have done so for many years. Before commenting on climate science I felt I should investigate the claims and the original data beforehand, which led me to a sceptical position. I am also quite experienced with modelling, including iterative and statistical modelling, and I’ve built and audited models for large corporate projects. The primary problem with the climate models associated with the IPCC is the ‘omitted variable bias’. In this case the omitted variables are the overall solar effect (as encapsulated in the paper I linked – there are many other papers around on this topic) and the ocean cycles. If these are left out the CO2 variable tends to come out too high, which is where Matt Ridley is coming from. As far as I can tell the sensitivity numbers he cites now include some of the ocean or solar effects, but clearly (to me) not all. But that illustrates what happens when the omitted variable is subsequently included in such a model.

If you want a fairly short summary of the climate sceptics’ hypothesis the write up by Dr David Evans is a good one. Also if you would like links or citations covering the areas I mentioned let me know.

And finally a last apology – I did not actually watch Dr Pierrehumbert’s video (I very rarely watch any videos of any kind), although I have read short summaries of it elsewhere.

wmmbb - December 20, 2012

Your comment is appreciated Bruce.

I was not concerned by the comments by the Catallaxy crowd. I expected them. As you mention there is some advantages in the free for all. I had not realized that Skeptical Science and Real Climate don’t allow alternative views to be expressed. By contrast I was quite off topic.

Since I rely on the internet for my news, I have to make sure that get access to the presentation of other views.

I notice that some of Dr Evan’s claims have attracted the attention of Skeptical Science.

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